I’m going to be building a rowing shell (22’ long and 2” wide) using the “strip-built canoe”construction, rather than the “stitch-and-glue” construction in the plans I have. Since the boat will be 22 feet long, and I’m not going to be able to get wood that long, I’m going to have to make joints.

I’d like some comments as to which might be the best type of joint to use. The strips will be 1/2” wide and 1/4” high by an unknown length. During construction of the boat, the strips will be placed strip-to-cove, and no lengthwise joints should be beside the neighboring strip. The reason for this type of construction is to make it easier to go around curves without leaving gaps.

I know that a simple butt is out of the question, as there is not enough surface to hold well. Thus, I am considering whether a lap joint or a lock joint made with my router might be better.

I realize that a simple lap joint would give the extra glue surface but then, what would be the angle that I should I use?

Since I am going to be doing a lot of strip routing (each strip will have bead on one edge and a cove on the opposite edge) adding to my router work by trying to rout a lock joint as well, might just use up too much time and effort if the lap joint will suffice.

Any suggestions? Are there any other joints I should consider for this? Any help would be appreciated

Brian75137 (in Denver, CO)

-- Brian now in Albuquerque, NM

9 replies so far

I vote for a keyed scarf joint. Goggle books has The elements of boat strength: for builders, designers, and owners By Dave Gerr that you might want to check out. Where you going to put this boat? I’ll come cheer.

Kaybee:I guess that I’ll put the boat in any good sized pond or lake I can find. There are a lot of lakes around the Denver Area, where I live, but I don’t want to go where there are a lot of motorboats, since there is always some anal orifice who things it’s fun to swamp a boat with only 4” of free board.

I guess that I’ll probably use scarf joints and hope that there’s enough gluing surfacewith a 10 degree scarf on a piece of wood that only 1/2” wide. Any ideas how I’ll be able to do a 10 degree scarf on any size lumber. I may have to make the scarf before I cut my 1/2” wood into 1/4” strips. What do you think?

i had to do lofting years ago for 100’ plus ships , and made myself a batten from 3/4 ” stock .i made a sliding jig for the tablesaw that i could run all the ends of my square stock thru .after glue up , i ran all 4 sides thru the planer ( 1 face , 1 edge , then the other face and edje ) to make it square at 5/8 ” and 100” feet long .it took 6 guys to feed it into the lofting area , but made the fairest curves they had ever had . it’s probably still in use today !make a sled that works off the miter slot , with a rail for the angle and length of the scarf and maybe a hold down for the piece and slide it into the blade,every end was ready for glue ,use two stops , and you just put in your piece and slide it thru the stops , and cut where you want .

-- david - only thru kindness can this world be whole . If we don't succeed we run the risk of failure. Dan Quayle

Firstly, I only have an 18×18 garage in which to do my wood working, so I’m going to have to build a workshop building or rent one. I am in the process of designing a 20’x32’ workshop, to be built with 4×8 sheets of plywood. The whole thing will be modular and will be bolted together. That way, if I have to move elsewhere, I will be able to take it apart and take it with me, wherever I go.

There willl be 20 floor modules arranged in 4 rows of 5 sheets, and the side walls will be 4×8 vertical modules – 8 modules to a side. There will be 2 types of wall modules one with and one without windows – 2 window modules per side. The roof trusses will be built so that they can be taken apart too. I know that this sounds like a lot of complicated work, but there’s a reason for it – I’m renting and I want to find a place where I can erect the building and not have to worry about a permanent foundation or having to leave it if I move elsewhere in the future.

Once I get the building erected, THEN I’ll be able to START building my boat. I’m sure that I’ll be able to find an adequate place to row on, just as long as it doesn’t have a bunch of ”- – - – -” people who would think that it would be cool to swamp this unusual looking boat.

Presently, I have built one each of the floor and side wall modules to see how difficult this will be to do. I’m also slowly collecting the types of tools and machines that I think I’ll need to build the boat.

If anyone is interested in learning more about my ambitious project, please don’t hesitate to contact me.

I”ll be using 3/4” lumber of random widths which have been planed to the rewuired 3/4” thickness abd then will be cutting 1/4” strips from this to get my 3/4×1/4 sized strips. Where my scarf joints will be, is at the end of these very flexible (at that point) strips so I will be able to end up with strips which are about 25’ long.

Handling them without breaking them is going to be a problem.

I do like your idea of using a dedicated sled to cut my scarfs, I’m going to have to build a very specialized one which will hold the 1/4” x 3/4” strips firmly in place while making the scarf joint cuts. Hmmmm is that another project on the horizon? I can just see it now – clamps and supports all over the place and series of trays or v-grooved shelving to hold both starting stock and finished lengths before they go to the router for a bead on one side and a cove on the other side (1/4” sides will be routed) (Maybe a 6-dimensional copy of AutoCAD would be usefull for drawing all this up)

Seriously, I’ll be keepinh everyone informed on this somewhat unusual project as I go along. I’m also going to be taking pictures along the way, too, so will eventually be posting that sort of progress reports.

Well, I took David’s suggestion and started to build a sled referencing my miter slide. I calculated and drew a 10 degree angle in AutoCAD, then transferred that to some MDF I had available. The miter bar (Rockler brand) is attached to the underside and a piece of MDS about 3 inches high is screwed on at the 10 degree angle. I will use a piece of wood cut to 1/4 inch, as a template and then screw another piece of MDF up to it so that I have a 1/2” piece of wood sandwiched between the 2 pieces of MDF. I’ll be set up so my saw blade will then be able to put a 10 degree taper (scarf) on any of the 1/2” strips I’ll be making for the rowing shell. (I will be tapering the 3/4 wide side of the strip). I just have to shove them into the channel between the MDF pieces to where the saw will cut off the right amount.

I know that the height of the MDF on both sides of the strip is a little high, but I thought that that would serve to keep the pieces upright as I cut them and I would not have to clamp them in place for each cut. A quick shove of a small wedge in the backside of the jig will keep the strip in place for the miter cut.

Dave, thanks for the suggestion. I tried the jig out and it seems to work exactly as I planned it.

I guess that the next Jig I build will have something to do with routing a bead on a bunch of strips. followed by routing a cove on the other side. Wow! I’ll be making a LOT of sawdust.

Well, the sled didn’t work out as well as I wanted. The ends ofthe scarf joint is not straight across and would require some good amount of sanding to get it smooth. I talked to my local woodworking toosales person and he suggested that I use a finetooth (80 Teeth) blade in my chop saw to make the scarf joint. He demoed the idea with a piece of 1/2×1/4 wood that I had brought in to show him my problem. We took the stick and madea cut with a 72 tooth blaed ha had on his chop saw and thecut was remarkedly good. I’ll get a 80T blade for my chop saw when I get ready to make the scarf joints. First, I have to get a good place for a workshop, then set up my shop, then get the wood I’m going to use, then cut my 1/4” strips off of the 3/4” boards, then put a bead on one edge of the strips and a cove on the opposing edge, THEN I’ll make my scarf joints. Along with setting up my strongback and cutting out my boat forms, this should opccur about 1-2 years from now.

I havean offer to exhibit my boat when I get it finished, in the Woodworkers show in Denver, either in 2011 or 2012 – whenever it’s ready. I will take pictures as I go along in making the boat, and will be one of the presenters at the show, to discuss something that most woodworking participants don’t think about doing. Building furniture is something that I’m going to do in the future, but, for now, doing the boat is my prime concern.